The invention relates to a hinge assembly for use in a space structure. Furthermore, the invention relates to a space structure which is equipped with a hinge assembly of this kind.
At present, virtually all spacecraft are solar powered. The solar cells used are typically triple junction solar cells based on III-V semiconductor with an efficiency of 30% under the AM0 spectrum in space. But even with these high efficiency cells, the available surface area on currently used satellite structures usually is not sufficient to meet the power demand of most satellite payloads. Therefore, deployable structures are required. In a typical solar array, individual panels having a size compatible with a satellite sidewall are interconnected by hinges such that the entire assembly can be folded towards the satellite sidewall during launch. Once on station, the array can be unfolded into its final configuration. In most designs, the hinges between two panels have to provide the driving torque for the deployment, a locking mechanism to fix the panels at the desired deployment angle, typically 180°, as well as sufficient stiffness in the deployed configuration. The most widely used hinge type for this application consists of two separate elements which are joined by a fixed axis of rotation. A separate coiled spring provides the driving torque for the deployment. An electrical connection between adjacent panels of the solar array typically is established by separate wiring elements which may, for example, be designed in the form of a wire bundle located in the axis of rotation of the hinge. Alternatively, planar wire configurations may be used to electrically connect adjacent panels of the solar array.
US 2002/0194702 A1 describes a deployment hinge for interconnecting and deploying panels from a stowed configuration into a deployment configuration. The hinge is designed in the form of a flat plate and made of a superelastic shape memory alloy such as Nitinol having a large elastic strain limit for enabling the hinge to bend around a small radius during stowage and flexible return to a trained rigid hinge position. The hinge is conductive enabling use of the hinge as a conductor for routing power through multiple solar cell panels interconnected by the hinge forming a hinged solar cell array that is deployed when the hinge is released from the bent stowed configuration to the rigid deployed configuration. The hinge further functions as a latch to lock the panels in place.
U.S. Pat. No. 9,048,530 discloses a deployable flat panel array, wherein at least two panels are coupled together via a carpenter tape hinge which is suitable to release stored energy to deploy the flat panel array from a packed position.
WO 99/60860 A2 relates to a hinge for deploying an object which includes at least one flexure member which is capable of moving from a first, folded configuration to a second, straightened configuration. The hinge further comprises a controller for controlling the movement of the first flexure member as the first flexure member moves or reconfigures from the folded configuration to the straightened configuration. The first flexure member may be made of a shape memory alloy and may have an arcuate cross-sectional configuration. The controller may comprise a means for absorbing stored energy of the first flexure member as the first flexure member moves from the first, folded configuration to the second straightened configuration. The hinge is connected to an electric source which supplies electric current to the hinge to drive the deployment of the object.